Target versus non-target analytical approach for describing metabolism of anthocyanins in rat

Understanding biochemical pathways involved in metabolism of natural polyphenols in mammals might represent one of the major goals of future research in this field. Epidemiological, clinical and experimental studies have shown that the dietary intake of flavonoids confers protection against many chronic diseases. Anthocyanins are among the most common flavonoids in human diet. Following their oral ingestion they are rapidly detected in plasma and organs both as intact compounds and as metabolites of phase 1 and phase 2 biotransformation. However, at present, the detailed metabolic pathways of anthocyanins in mammalian organisms still remain largely unknown. In our study cyanidin 3-glucoside was administered at low dose intravenously in anaesthetised rats. The tissue distribution and metabolism of cyanidin-3-glucoside was investigated using both target and non-target UPLC-MS and UPLC-Q-TOF experiments. With the target approach, cyanidin 3- glucoside and its metabolites were investigated in plasma, liver, kidney and urine. It was found that the kidney was the organ accounting for most of cyanidin 3-glucoside uptake and metabolism. The further aim of this work was also to apply non-target experimental approach in order to investigate diverse tissues and organ-specific metabolites which might also be differentially expressed in blood, kidney, liver and urine.